Hot-air fubhace



unrmn STATES rATENrorFioE.-

HOT-AIB FURNACE.

Specification of Letters Patent No. 8,104, dated May 20, 1851. i

To all whom it may concern Be it known that I, SAMUEL PIERCE, of Troy, in the State of New York, have invented a new and useful Improvement in Hot-Air Furnaces for Heating Houses, &c., and that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, making part of this specification, in which- Figure l is a perspective view with part of the surrounding masonry removed; Fig.

2, is a horizontal section taken at the line l A, a, of Fig. 3; Fig. 3, a 'vertical section taken at the line B, 5,*of Fig. 2;y and Fig. 4, a cross vertical section taken at the line C, c, of Fig'. 3.

The same letters indicate the figures. l

The object of my invention is so to construct a hot air furnace that the heated like 'parts in all gaseous products of combustion, in passing y culiar arrangement of these metalfsurfaces,

through from the re chamber to the chimney, shall not only pass in contact with a large extent of metal surface to heat the surrounding atmospheric air, but by a peand the passages throitgghV I' which .,the gaseous products of kcombustion pass to retain the heat in contact with them for a sueient length of time to give out the heat,

and to eii'ect this without impeding the draft. All this l effect by connecting with the re chamber of the furnace, a series of four, more or less, vertical heat-ingv chambers, each presenting two large flat surfaces outside to the air which is to be heated and a thin space within for the reception and passage of the heated products of combustion. The first of this series communicates with the furnace by means of two pipes or co llars, this first chamber communicating in the same manner and in the same lines with the second, the second with the third, this connection not being carried through to the last of the series. And the said chambers at or near the bottom communicate with each other throughout the series by collars or pipes, and the last of the series communicates with a pipe leading to the chimney, and then again the said series of chambers communicate together at or'near the top by a series of pipes or collars and the last of the series with the exit pipe leading to the chimney; but the communication between the two last of the series, or.

between the last and the exit pipe, is only about half the capacity of) the others for the purpose of checking the vescape of the products of combustion )directly into the chimney and thereby inducing'aportion of the escape from the bottom. It is this peculiar arrangement ofthe heating chambers with eachother and the furnace in combi nation with the .method of connecting them together and-withthe furnace and with the;

exit pipe, which constitutes my invention. Y n

In the accompanying drawings a repre? sentsv thefurnace containing in the usual manner a re pot b,- feeding door c and ash pit (l. The 'furnace just'abovethe top Ais cast with two swells or enlargements'c, e, one on each side, Vthe rear end of each of the nature o'f which is cast `with a collar f, to fit by ap'- propriate joints corresponding collars g, g, cast onto 'the front face of the first heating chamber 71.. Theseheating chambers L, aie each made Vof two plates cast with a rim all around and a fianch by which the two are unitedaand secured by bolts' ,:so as to make a close Ajoint; and when put together there is a thin space between lthe two plates con` stituting 4the. heating chamber which being` very vnarrowreceives avery extensive but.

thin film" of the gaseous Vproducts of com.-

bustion, whichbeing very' thin, will give w out` its sensible heat readily .to the' metal. c

Y All the plates except the frontplate of the first-and the Aback plate of the last of the series of chambers are cast each with two collars g,'g, like the first, and with. one collar y' near the upper rim and a like one'k neai'the lower rim. So that when these collars are all put together and thewholel securedtogetherby bolt rods Z, there Awill be two passages directly through from the furnace'through the holes in the collars g, g, to the third chamber, the two last collars notbeing perforated like Athe others. And

there will be another passage through holes inthe Vcollars Ic," near the bottom connecting with two collars j', and 7c', and in the sameline with the corresponding collars on the other plates, which last collars are connected ,c all thechambers together, and in likeA man- Vner a similar connection at top through the with corresponding collars on a vertical exit pipe m which communicates in the usual manner with the chimney. The exit p-ipe is provided with a collar a at the back in a line with the series of collars k, and this collar n, is provided With\a cap Which When removed gives access to all the chambers, which by their peculiar construction shall deposit all soot and ashes at the bottom and in the pipe formed by the series of collars k, So that by this means all the chambers can be readily cleansed.

,Instead of closing the apertures of the col lars g, g, which form the connections with the last of the series of chambers, these apertures may be 'opened provided this last n chamber be connected With the exitpipe at the top and bottom, and the top aperture be made of less capacity, instead of having this reduced capacity between the last of the series and the one preceding it.

From the foregoing it will be seen that When the gaseous products of combustion pass from both sides of the furnace into the first chamber, a portion of the heated gases will spread and lill the entire chamber, and the rest Will continue through the collars g, g, into the second chamber, a portion Will then spread in the second chamber and so on. A portion of the gases Which spread out in the first chamber will escape'from the top and bottom connections into the second chamber and so on throughout the series. But as by rarefaction all heated gases seek Ito ascend and to escape through the highest aperture, if the last of the series of chambers were connected With the exit pipe at top byan aperture of sufficient capacity, none or but a Very small portion of these gases Would descend to the bottom of the chambers, hence I make the aperture Which Connects the next to the last With the last of the series of chambers at top or th last of the series of chambers With the exit pipe ot' only one half (or thereabouts) the capacity of the other apertures or passages, which has the elfect to check the escape there and compe-lv a portion of the gases to descend and escape into the exit pipe through the lower connection. In this way I insure the spread and circulation of the gases in" thin films throughout all and every portion of the chambers constituting the series while at the same time they are retained Within the chambers suiiciently long to give out the heat required, and this too without injuriously checking the draft. Each chamber constitutes in fact a hollow rinV with an open space 0 in the middle in whic space a pan containingwater may be placed, to furnish the requisitemoisture. y

The Whole apparatus is surrounded b masonry p, of the usual construction an which therefore need not be described. o

Vhat I claim as my invention and desire to secure by Letters Patent isi The arrangement, substantially as herein described, of the heating chambers in connection with the furnace, when this is combined with the method, substantially as de scribed of connecting the heating chambel'i with each other, with the furnace andwith the exit Vpipe leading to the chimney, whereby the gaseous products of combustion are carried into and through, and made to` spread M out in thin films in, the said heating chain-` bers, and therein retained to give out heat Without seriously impeding the draft, sub stantially as described. Y f

SAMUEL PIERCE.

TWitnesses W'M. H. BISHOP,

CASPER BROWNE. 

